1. Field of the Invention
This invention pertains to stents for use in intraluminal applications. More particularly, this invention pertains to a novel structure for such stents.
2. Description of the Prior Art
Stents are widely used for numerous applications where the stent is placed in the lumen of a patient and expanded. Such stents may be used in coronary or other vasculature, as well as other body lumens.
Commonly, stents are cylindrical members. The stents expand from reduced diameters to enlarged diameters. Frequently, such stents are placed on a balloon catheter with the stent in the reduced-diameter state. So placed, the stent is advanced on the catheter to a placement site. At the site, the balloon is inflated to expand the stent to the enlarged diameter. The balloon is deflated and removed, leaving the enlarged diameter stent in place. So used, such stents are used to expand occluded sites within a patient""s vasculature or other lumen.
Examples of prior art stents are numerous. For example, U.S. Pat. No. 5,449,373 to Pinchasik et al. teaches a stent with at least two rigid segments joined by a flexible connector. U.S. Pat. No. 5,695,516 to Fischell teaches a stent with a cell having a butterfly shape when the stent is in a reduced-diameter state. Upon expansion of the stent, the cell assumes a hexagonal shape.
In stent design, it is desirable for the stent to be flexible along its longitudinal axis to permit passage of the stent through arcuate segments of a patient""s vasculature or other body lumen. Preferably, the stent will have at most minimal longitudinal shrinkage when expanded and will resist compressive forces once expanded.
The present disclosure relates to a stent including a stent body having a stent axis. The stent body includes structural members that define openings through the stent body. The structural members are provided with regions having different widths. The relative sizes of the widths are selected to control the length of the stent body as the stent body is radially expanded from an un-deployed orientation to a deployed orientation. In one embodiment, the regions having different widths are provided by tapering the widths of selected segments of the structural member. In a preferred embodiment, the relative sizes of the widths are selected to minimize or eliminate length changes as the stent body is expanded from the un-deployed orientation to the expanded orientation.